Convoy smoke...
 

From my (granted limited) reading, I'm led to believe that convoys, particularly those with a high number of coal fueled ships, were covered in a continuous pall of smoke, in some cases visible up to 50nm distance.

This is recognised somewhat in SH5 by the 'smoke on the horizon' announcement, but it isn't depicted in the game.

Is there a mod that addresses this? or, if not, what are people's opinions on how hard it would be to implement?

I wouldn't mind turning my hand to it if people think it wouldn't be too hard and if I could get some pointers.

have a look here - http://www.subsim.com/radioroom/showthread.php?t=166121

Thanks Volodya, appreciated.

I've been trying it out, and it's a great mod.

I was thinking more in terms of a general haze over convoys. I'll go see if I can find some photos to see if there was a haze, and to what extent it existed.

This sort of haze ?
http://www.subsim.com/radioroom/showthread.php?t=202272

LOL... that's the after haze Sober. ;)

Maybe try that: http://www.subsim.com/radioroom/showthread.php?t=166121